Since the watering of plants in pots is a burden, self-watering devices of various kinds attempt to alleviate the continuous task of watering on a regular basis. One proposed solution is divulged in the PCT International Publication No. WO 01/35724 A, by A. Gelfer, describing a dedicated planter containing one or more pots, where watering liquid is conducted from containers of liquid via pipes to the plants in the pot(s). Although effective, that dedicated planter is rather complicated and expensive to build.
A self-watering planter is disclosed in U.S. Pat. No. 4,324,070 to Swisher, which “ . . . comprises a water reservoir 3, an absorbent mat 5 disposed on a removable lid 7, and a separable plant container 9 containing growing media 11 . . . ”. The reservoir is described as: “Water reservoir 3 includes . . . an open top portion 15 . . . An annular recessed area 17 is formed about the periphery of open top portion 15. Annular area 17 includes one or more watering openings 19 formed therein . . . ”. Details of the lid state: “Lid 7 also includes an opening 23 formed therein for receiving a wick portion 25 of absorbent mat 5.”
As to the plant container: “Plant container 9 includes a recessed base 29, . . . recessed by a downwardly extending rim 37 formed as part of the lower portion of side walls 31. One or more openings 39 are formed in base 29 . . . complementary to water-receiving openings 19 of water reservoir 3.”
Swisher further explains: “When lid 7 and plant container 9 are assembled atop water reservoir 3, rim 37 of container 9 rests along an outer portion of recessed annular area 17.”
According to the quotations listed above, the self-watering planter by Swisher suffers from several shortcomings. First, both the water reservoir 3 and the separable plant container 9 must be manufactured to description so as to match. Second, the separable plant container 9 assembled atop water reservoir 3 creates a tower of questionable stability, especially when used outdoors in windy conditions. Third, the invention is not applicable for use by a plant grower, who is at the origin of the potted plant life cycle.
U.S. Pat. No. 1,216,642 to White discloses “A vertical tube 10 fixed intermediate of its ends,” with the upwardly projecting portion of the tube extending “into the earth within said pot”, and “ . . . a length of sponge (11) or other absorbent material extending through the tube 10 . . . ” into the water, and “ . . . also projects outwardly from the upper end of the tube 10 into the flower pot.” Since the tube 10 is fixed it cannot be easily and reversibly removed or replaced. Furthermore, the amount of water absorbed by the sponge 11 and by capillary attraction cannot be dosed, regulated and controlled. Moreover, the sponge 11 extending into the earth will become clogged by the roots of the plant.